First-Ever Mapping of Photosynthesis in Fastest Growing Alga in the World

What causes a particular alga to be crowned “the fastest growing plant cell in the world?” A new study involving a Tel Aviv University researcher set out to track the photosynthetic properties of the alga Chlorella ohadii, a type of green algae considered to be the fastest growing plant cell.

The study’s findings indicate that the main factors behind the plant’s rapid photosynthesis rate lie in its efficient metabolic processes. The researchers found that this alga has a unique ability to elicit a chemical reaction in which it is able to efficiently and quickly recycle one of the components used by an enzyme called RuBisCO, in a manner that significantly speeds up the photosynthetic processes.

In the framework of the study, the researchers sought to examine whether it is possible to improve the efficiency of photosynthesis in plants, an energetic process that occurs in nature. To try to answer this question, the researchers decided to focus on green algae, particularly the Chlorella ohadii variety. This alga is known for its ability to survive in extreme conditions of heat and cold, which forces it to exhibit resilience and grow very quickly.

The researchers assessed that a better understanding of Chlorella ohadii (named after the late botanist Prof. Itzhak Ohad) would make it possible to improve the efficiency of photosynthesis in other plants as well, and in turn to develop new engineering tools that could provide a solution for sustainable food.

In the process of photosynthesis, plants and algae convert water, light and carbon dioxide into the sugar and oxygen essential for their life processes. The researchers used innovative microfluidic methods based on complex physical, chemical and biotechnological principles in order to provide the algae with carbon dioxide in a measured and controlled manner and monitor the photosynthesis “online.”

By using a comparative analysis, the researchers identified a fundamental difference in the photosynthesic processes carried out in in green algae compared to the model plants. They believe that the difference lies in variations in the metabolic networks, a deeper understanding of which will help in developing innovative engineering solutions in the field of plant metabolism, as well as the optimal engineering of future agricultural products.

“Past empirical studies have shown that photosynthetic efficiency is higher in microalgae than in C3 or C4 crops, both types of plants that have transport systems but which are completely different in terms of their anatomy and the way they carry out photosynthesis,” Dr. Haim Treves explains. “The problem is that the scientific community does not yet know how to explain these differences accurately enough.”

Dr. Treves adds, “The toolbox we have assembled will enable us to harness the conclusions from the study to accelerate future developments in engineering in the field of algae-based sustainable food as a genetic reservoir for plant improvement; monitoring photosynthetis is a quantitative and high-resolution process, and algae offer an infinite source of possibilities for improving photosynthetic efficiency.”